The present invention relates to castors, and more particularly to a castor mechanism that permits a castor to be moved from an operative position to an inoperative position.
Articles of furniture and other heavy objects are often provided with castors so that they can be moved more easily. The castors do not, however, provide a base for the article that is as solid as the legs or bottom surface of the article itself. It is desirable, therefore, that the castors be made retractable to provide better support and to lower the article to its normal height when it is not being moved.
Retractable castor mechanisms that have been proposed previously are often difficult to operate. Many require that the article be lifted off the castor which is then secured in a retracted position. This arrangment is unsatisfactory because the desired to avoid lifting the article is often the reason for providing castors in the first place. Even if the article is not heavy, it is usually difficult for one person to simultaneously lift it and operate the castor mechanism. Other difficulties arise because a single person cannot operate more than one such mechanism at a time, while most articles require four or more castors for adequate support.
Some previously known castor mechanisms have included jacks by which the article can be raised and lowered, but such mechanisms are often unduly complex and difficult to use, especially in a confined area. Moreover, most previously known castor mechanisms required that the user be able to reach the mechanism to extend or retract it, and the location of the mechanism under the article and near the floor is often not conveniently accessible.
A principal object of the present invention is to provide an improved castor mechanism that can be operated conveniently by forces applied to the article on which the castor is mounted, without direct access to the castor mechanism itself.